In processes as presently used for the permanent deformation of hair, the desired deformation is achieved by chemical methods. Initially, the disulfide bridges of the hair keratin are split by reduction under the influence of a suitable reducing agent. The hair is then brought into a new form and subsequently fixed in its new form by treatment with an oxidant, wherein the split disulfide compounds are bonded again. Primarily mercapto-compounds, particularly salts or derivatives of thioglycolic acid, such as ammonium thioglycolate, ammonium thiolactate and glycerin monothioglycolate are used as reducing agents, and in addition certain sulfites, preferably ammonium sulfite. Hydrogen peroxide is, primarily, used as suitable oxidant.
Subsequent to the permanent deformation, a thorough rinsing of the hair with water is done, in order to remove residues of the reducing agent and oxidant that have remained in the hair. Such residues will remain particularly when insufficient care has been taken in respect of the quantities of the reducing agent or oxidant used, when not paying exact attention to the required application period, and when there is insufficient final rinsing. Residues of the reducing agent and oxidant can, however, not be completely removed even if thorough final rinsing has been made. This is due to the characteristic of the hair keratin which will retain such residues by a rather firm bond.
Leaving such residues in the hair has an extremely disadvantageous effect upon the structure and appearance of the hair, and it will lead to considerable damage to the hair. Such damage becomes apparent particularly by the hair becoming brittle, by a reduction in the hair strength and furthermore by a decrease in the ease of combing and loss of the natural hair luster. It is to be added hereto that the durability of the permanent deformation will be reduced by residues of the reducing agent, whilst residues of the oxidant will effect an undesirable brightening of the hair coloring.
If the mercapto compounds, primarily used today, are used for the permanent deformation of hair, an unpleasant odor will furthermore by present after treatment, which can be covered by perfuming agents only with difficulty.
It was, therefore, the task of the invention, to find a means for the treatment of permanently deformed hair, by which the aforenoted disadvantages would be avoided to a great degree.